Date:   Sun, 19 Feb 2023 19:16:57 +0000
From:   Thomas =?utf-8?Q?Wei=C3=9Fschuh?= <thomas@t-8ch.de>
To:     Willy Tarreau <w@1wt.eu>
Cc:     Vincent Dagonneau <v@vda.io>, linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH 2/4] tools/nolibc: add integer types and integer
 limit macros
Message-ID: <dab2632a-262d-402c-8d86-5e8965b124f6@t-8ch.de>
References: <20230219185133.14576-1-w@1wt.eu>
 <20230219185133.14576-3-w@1wt.eu>
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On Sun, Feb 19, 2023 at 07:51:31PM +0100, Willy Tarreau wrote:
> From: Vincent Dagonneau <v@vda.io>
> 
> This commit adds some of the missing integer types to stdint.h and adds
> limit macros (e.g. INTN_{MIN,MAX}).
> 
> The reference used for adding these types is
> https://pubs.opengroup.org/onlinepubs/009695399/basedefs/stdint.h.html.
> 
> Note that the maximum size of size_t is implementation-defined (>65535),
> in this case I chose to stick with what the kernel uses in
> linux/include/uapi/asm-generic/posix_types.h: unsigned int on 32bits and
> unsigned long on 64bits.
> 
> Signed-off-by: Vincent Dagonneau <v@vda.io>
> [wt: size_t is always ulong since it matches the word size on all archs
>  we care for; calculate the SIZE_MAX, INTPTR_MIN and INTPTR_MAX based on
>  the compiler-provided __LONG_MAX__]
> Signed-off-by: Willy Tarreau <w@1wt.eu>
> ---
>  tools/include/nolibc/stdint.h | 51 +++++++++++++++++++++++++++++++++++
>  1 file changed, 51 insertions(+)
> 
> diff --git a/tools/include/nolibc/stdint.h b/tools/include/nolibc/stdint.h
> index 4ba264031df9..5f1adf9316ca 100644
> --- a/tools/include/nolibc/stdint.h
> +++ b/tools/include/nolibc/stdint.h
> @@ -21,4 +21,55 @@ typedef unsigned long     uintptr_t;
>  typedef   signed long      intptr_t;
>  typedef   signed long     ptrdiff_t;
>  
> +typedef   int8_t       int_least8_t;
> +typedef  uint8_t      uint_least8_t;
> +typedef  int16_t      int_least16_t;
> +typedef uint16_t     uint_least16_t;
> +typedef  int32_t      int_least32_t;
> +typedef uint32_t     uint_least32_t;
> +typedef  int64_t      int_least64_t;
> +typedef uint64_t     uint_least64_t;
> +
> +typedef  int64_t           intmax_t;
> +typedef uint64_t          uintmax_t;
> +
> +/* limits of integral types */
> +
> +#define        INT8_MIN  (-128)
> +#define       INT16_MIN  (-32767-1)
> +#define       INT32_MIN  (-2147483647-1)
> +#define       INT64_MIN  (-9223372036854775807LL-1)
> +
> +#define        INT8_MAX  (127)
> +#define       INT16_MAX  (32767)
> +#define       INT32_MAX  (2147483647)
> +#define       INT64_MAX  (9223372036854775807LL)
> +
> +#define       UINT8_MAX  (255)
> +#define      UINT16_MAX  (65535)
> +#define      UINT32_MAX  (4294967295U)
> +#define      UINT64_MAX  (18446744073709551615ULL)
> +
> +#define  INT_LEAST8_MIN  INT8_MIN
> +#define INT_LEAST16_MIN  INT16_MIN
> +#define INT_LEAST32_MIN  INT32_MIN
> +#define INT_LEAST64_MIN  INT64_MIN
> +
> +#define  INT_LEAST8_MAX  INT8_MAX
> +#define INT_LEAST16_MAX  INT16_MAX
> +#define INT_LEAST32_MAX  INT32_MAX
> +#define INT_LEAST64_MAX  INT64_MAX
> +
> +#define  UINT_LEAST8_MAX UINT8_MAX
> +#define UINT_LEAST16_MAX UINT16_MAX
> +#define UINT_LEAST32_MAX UINT32_MAX
> +#define UINT_LEAST64_MAX UINT64_MAX
> +
> +#define SIZE_MAX         ((__SIZE_TYPE__)(__LONG_MAX__) * 2 + 1)

Nit: size_t would look nicer than __SIZE_TYPE__.
Also SSIZE_MAX could be added.

> +#define INTPTR_MIN       (-__LONG_MAX__ - 1)
> +#define INTPTR_MAX       __LONG_MAX__
> +#define UINTPTR_MAX      (SIZE_MAX)

Braces seem unnecessary.

> +#define PTRDIFF_MIN      INTPTR_MIN
> +#define PTRDIFF_MAX      INTPTR_MAX
> +
>  #endif /* _NOLIBC_STDINT_H */
> -- 
> 2.35.3
>